提出一种新的同时测量火焰温度场、颗粒浓度场和气体浓度场的非接触光学测量技术．在稳态火焰周围安装4台电荷耦合器件(CCD)，火焰的多光谱图像是由在 CCD 前安装的滤波片拍摄得到，使用的滤波片通过波长分别为0.436,µm(蓝光)、0.700,µm(红光)和1.87,µm(水吸收峰)．建立了一个在三波长下的辐射反问题模型．通过水对波长的选择吸收性分离出颗粒吸收系数和水的吸收系数．利用统计窄带模型得到水浓度，利用 Mie 散射理论得到颗粒浓度．模拟两个算例，得到从水浓度场、颗粒浓度场到温度场重建误差依次减小．当颗粒体积分数低于1×10-6时，水浓度场可以准确重建出来．如果要精确测量水浓度，则需要辐射路径测量误差不大于1%,．%An original technique is presented for noncontact three-dimensional temperature,particle concentration and water vapor concentration field measurement in steady flame using radiative information captured by four cameras.The multi-spectral flame images are obtained by cameras which are equipped with three filters whose center wavelengths are 0.436,µm(blue),0.700,µm(red)and 1.87,µm(water absorption peak),respectively.An inverse problem model is built to calculate the radiative transfer equation under three wavelengths.The particle absorption coefficient and the water vapor absorption coefficient are separated through water by wavelength selective absorp-tion.The statistical narrow band(SNB)model is introduced to obtain gas concentration,and the particle concentra-tion is calculated by Mie theory.Two numerical simulation cases are adopted to validate the technique.It is found that temperature reconstruction is the best,followed by particle concentration reconstruction and then water concentration reconstruction.When the particle concentration is below 1×10-6,the water concentration could be reconstructed successfully.The length error of radiation route should be below 1%, for the accurate water concentration reconstruc-tion.
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